Start with the right checks.
A blank preview can come from a closed cover, another app using the camera, or the wrong camera selection. It does not automatically mean the camera is broken.
What to do next.
Open the camera cover and reconnect an external webcam directly to the computer.
Close other apps that may be using video, then reopen Teams.
In Teams Settings > Devices, select the intended camera and check its preview. If using the browser, check the site’s camera permission.
Check the computer’s camera privacy settings. Save your work before restarting the computer or installing available app and system updates.
Check the result.
Check the preview, then confirm the image appears in a call you intended to join.
Stop and get help if…
The camera also fails outside Teams, permissions are managed, or a remote desktop session is involved. Support may need to check the device or company configuration.